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use std::{error, fmt};

#[derive(Debug, Clone)]
/// Possible error states for the hashing.
pub enum Error {
    /// The allowed number of leaves cannot be greater than the arity of the tree.
    FullBuffer,
    /// Attempt to reference an index element that is out of bounds
    IndexOutOfBounds,
    /// The provided leaf was not found in the tree
    LeafNotFound,
    /// Other errors
    Other(String),
}

impl error::Error for Error {}

impl fmt::Display for Error {
    fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
        match self {
            Error::FullBuffer => write!(
                f,
                "The size of the buffer cannot be greater than the arity of the merkle tree."
            ),
            Error::IndexOutOfBounds => write!(f, "The referenced index is outs of bounds."),
            Error::LeafNotFound => write!(f, "The provided leaf is not present in the tree."),
            Error::Other(s) => write!(f, "{}", s),
        }
    }
}